Machine for shredding leather



Sept-11 1934.

E. G. HOWES, JR ETAL MACHINE FOR SHREDDING LEATHER Filed July 6, 1932 2 Sheets-Sheet l Sept. 11, 1934. E. G. HOWES, JR., ET AL v MACHINE FOR SHREDDING LEATHER Filed July 6. 1932 2 Sheets-Sheet 2 i 5%: =5 b m z z s= s s Patented Sept. 11,1934

PATENT OFFICE momma FOR. SHREDDING LEATHER Ernest G. Howcs, Jr., Hingham, and Edward 0. Bartlett, Cambridge, Mass., assignors to Howes Bros. Hide 00., Boston, Mass., a corporation of Maine Application July 6, 1932. Serial No. 621,063

4 Claims., (01. 83-11)" V This invention relates to a machine for shredding leather, and more particularly for defibrating the leather in contradistinction to grinding or powdering it.

5 Grinding machines of various types have heretofore been used to shred leather but the product from such treatment has generally been dust or short fibers. While such product has been suc-" cessfully used in the manufacture of many articles, its use is open to the objection that the articles so made have not the toughness possessed by the original leather. Moreover, it has been found impossible to weave the product into fabric without employing cotten or other fibrous 1 material as a base.

The object of this invention 'is to provide a machine in which the body of the leather is shredded or torn apart and the fibers extracted therefrom in approximately their original length,

90 such operation being performed quickly, cheaply and efficiently upon all kinds of leather regardless of size and composition, and particularly upon the long fibered leather made from the cheeks and bellies of animals,

in arrangement and means for rapidlylrotating the cutters into yielding successive contact with different parts of the leather, thereby shredding .30 or tearing it apart and at the same time re- A further object of this invention is to provide a machine having a plurality of cutters staggered f as a screen 12. Suction is set up in the chamber 11 by a blower 15 of any desired type, the intake end of which is connected by a pipe 16 with a hopper 17 which receives the fibers discharged from the fibrating'chamber 1-1. The fibers drawn through the pipe'16 to the blower 15 are in the present instance discharged therefrom through a pipe 18 into a receptacle 19.

Mounted within the chamber 11 is a cutter 20 having cutter blades 21 thereon. Thecutter com- 55 prises a plurality of laterally spaced disks 22 into the space between each two disks one end of a cutter blade extends. Bolts 23 which pass through openings 24 in the blades and through the disks secure the blades-inposition, The 70 space between each pair of disks, issomewhat more than the thickness of the blades so thatith'e blades swing freely upon the bolts 23- and only assume the positions shown in Figs.-f2,3 and 5 under the action of centrifugal force whenth cutter is in rotation. The disks 22 are fixedupon a shaft 25 which is driven in any suitable, way, as by a motor 26 through a belt and pulley.assembly 27. .The shaft 25 also drives the blower 15 so that the parts of the machine move infi unison. The blades 21 as shown in Fig. -3 ar-eff not thin, but are on the contrary appreciably thick,-a thickness of one-quarter of an inch bing found desirable. Such blades are arranged in two rows, three in each row, and the. blades 85 fraining from severing the fibers transversely." in one row are staggered withrespectto the Other objects of this invention include the provision of means for supplying-a flow of air,

which imparts a whirling movement to the treat-,.

ed leather, to prevent undue grinding thereof and facilitate the removal of the fibers from the machine; and other features which will appear from a consideration of the following description and of the drawings which form a part thereof, 40 and in which:

Fig. 1 is an end elevation of ,a machine em bodying one form of this invention;

Fig. 2 is a side elevation partially in section of the fibrating portion of this machine;

Fig. 3 is an enlarged elevational view of the preferred form of the rotary cutter illustrating the staggered arrangement of the cutter blades; Fig. 4 is a plan view of the screen of the machine extended into a plane; and

Fig. 5 is a View similar to Fig. 2 of another embodiment of this invention.

The leather usually in the form of scraps is fed through a chute 10 into a chamber 11 where i it is .fibrated and the fibers discharged through perforations in a plate, hereinafter designated blades in the other row. The semi cylind rical screen 12 forms the. lower 1 half of the chamber 11 being secured against flanges 30, 31 projecting inwardly from the walls of the machine casing. Mounted above the flange 30 is a vertical plate 32,'the inner surface of which may be, as here showmcorrugated. An

'arcuate plate 33, mounted above the flange 31- and forming'a continuation of the screen 12 may 5 have its inner surface similarly treated. These plates'32 and 33 will be hereinafter referred to as cutter bars in accordance with the usual commercial practice, but it will be understood that this term does not limit them to plates having the inner surfaces corrugated, as here shown, and

41 and 42. An opening 43 in the wall of the compartment 41 provides a direct connection to the atmosphere for a reason hereinbelow set forth. The particular form of the perforations made in the screen is not of primary importance, but it is desirable, however, that the surface 44 of the screen against which the partition 40 rests be unperforated.

When the blower 15 and cutter 20 are set in operation cross currents of air, designated by arrows A, B and C, are set up in the chamber 11. The cutter 20 causes a rotation of air (arrow A) while the blower draws air through the perforations 38 of the screen 12 directly across the chamber from the open upper end (arrow B), and also from the perforations 36 of the screen (arrow C). Such currents keep the leather within the chamber and prevent its lodging in any portion thereof.

One theory of the action of the machine is that when the leather, usually in the form of scraps, is fed into the chamber 11 over the chute 10 some of it is first carried by the current A and one row of blades 21 against the cutter bar 32, and since its travel is retarded by the cutter bar, the blades will yieldably drag along the surface and act like a comb to remove some of the fibers thereof and carry them over the perforations 36, whereupon they are raised from the screen and the fibers follow the air currents C through the perforations 38 into the hopper. If the leather just treated remains against the cutter bar 32 until the second set of blades 21 arrives thereat, its surface will be given a second combing which. because of the staggered arrangement of the blades, will be spaced from the first. The leather not yet entirely fibrated will be dislodged by the second treatment and fall to the screen 12, along which it is moved by the blades and by the circular current A set up thereby. Any leather resting upon the portion 35 will be blown away by the air current C, but that resting on the portion 37 will obviously be held by suction and receive further combing treatment. At the cutter bar 33 the leather is further impacted during its passage thereover. The flow of current B from the inlet across the chamber to the portion 37 of the screen carries the fibers resulting from this treatment through the perforations 38. The rest of the leather falls by its own weight directly upon the screen 12 and is then either acted upon as pointed out above by the blades and carried to the cutter bar 33 at which it is fibrated, or else is carried thereto by the centrifugal current set up by the rotating cutterf The leather in the machine is thus subjected toa combing or tearing action due to the retardation of the leather by its contact with the walls of the chamber and the yieldable mounting of the blades. The cross air currents set up in the chamber prevent the leather from remaining in a particular location for any definite length of time and, moreover, since the blades are staggered, the chances of successive impacts upon the same areas of the leather are practically eliminated and the successive impact on the leather of both rows of blades would not result in grinding the leather to powder as would be the case if the blades were not staggered. Furthermore, one difficulty which has heretofore been experienced has been that the leather has been charred and scorched by heat generated through the frictional engagement of the blades and the leather. The creation of the air currents previously described and particularly the current designated by the arrows C assists in preventing such overheating of the leather and the resultant charting and scorching thereof.

As shown in Fig. 5, the portion 35 of the screen may be connected through a funnel 45 with a positive source of air supply (not shown), thus increasing the agitation of the leather within the chamber. Such an arrangement is particularly of value when leather having a high coefficient of specific gravity is being treated.

While two embodiments of this invention have been shown and described, we are not limited thereto, since other embodiments may be made without departing from the spirit and scope of the invention as set forth in the following claims;

We claim:

1. A machine for fibrating leather comprising a chamber in which the leather is treated, a rotatable cutter having at least two rows of cutter blades, the blades in one row being staggered with respect to the blades in the other row, the side wall of the chamber including a perforated plate or screen and a cutter bar, a hopper below the screen, a partition in the hopper and in contact with the perforated plate dividing the hopper into two compartments, and means for creating a flow of air through the screen into the chamber from one compartment of the hopper and through the screen from the chamber into the other compartment of the hopper to draw therein the fibers into which the leather is-resolved in the chamber by the action of the cutter.

2. A machine for fibrating leather comprising a chamber in which the leather is treated, a rotatable cutter having at least two rows of cutter blades, the blades in one row being staggered with respect to the blades in the other row, the side wall of the chamber including a perforated plate or screen and a cutter bar, a hopper below the screen, a partition in the hopper andin contact with the perforated plate dividing the hopper into two compartments, an opening through the wall into one of said compartments, and means for creating a flow of air through the opening into the chamber through the portion of the perforated plate above said compartment, and thence through the portion of the perforated. plate above the other compartment into that other compartment to draw therein the fibers into which the leather is resolved in the chamber by the action of the cutter.

3. In a machine for fibrating leather comprising a chamber in which the leather is treated. a cutter rotatable in the chamber, aplate forming a part of the wall of the chamber and having two perforated portions, the perforations in one portion being smaller than those in the other portion, a hopper below the plate, a partition dividing the hopper into two compartments and contacting with the plate so that one portion forms a part of one compartment and the other portion forms a part of the other compartment and means for creating a fiow of air into the chamber from one compartment through the perforations in one portion of the plate to agitate the leather fibers in the chamber and from the chamber into the other compartment through the perforations in the other portion of the plate to draw therein from the chamber the fibers into which the leather has been resolved by the cutter.

4. In a machine for fibrating leather compris-. ing a chamber in which the leather is treated, a cutter rotatable in the chamber, a plate forming a part of the wall of the chamber and having two perforated portions, the perforations in one portion being smaller than those in the other por- 150 tion, a hopper below the plate, a. partition dividing the hopper into two compartments and contacting with the plate. so that the portion having the smaller perforations forms a part of one compartment and the portion having the larger perforations forms a part of the other compart-' ment and means for creating a flow of air into the chamber from one compartment through the portion having the smaller perforations to agitate the leather fibers m the chamber and from the 

